Additive for Diesel Fuel

[GeorgeandAde]

Hi. I have a 2007 CRV 2.2 CDTI and was wondering the thoughts of other forum members regarding using the additives you can purchase to add to the fuel tank.
Does anyone have any experience of using them (good or bad)?
I understand they can help to keep the engine and components cleaner reducing the amount of carbon build up etc..
The car is mainly used for shortish journys to work on A roads(about 5 miles each way)and then approx.4 or 5 trips away with the van each year.
Would appreciate any feedback please,
Many thanks,Ade.

 

[seth1]

I wouldnt think the short journeys to work would help it much if has a filter fitted in the exhaust(dpf).As for the additive ive never used any and never needed it.I think its a bit of kidology,people add it and convince themselves it "feels" better.

 

[ProfJohnL]

There have been a number of tests carried out by magazines and other reputable organisations that do suggest some of the preparations might help to clean or at least reduce the deposition of rubbish in engines.

But all the preparations that claim performance enhancements were found to be virtually useless.

 

[seth1]

So after the magazines and other reputable souces had done their tests,did they not come up with something better than "might help" ?

 

[RogerL]

Both petrol-injection and diesel-injection engines can have their performance/economy eroded by deposits on the injectors which stops them closing fully and/or slows down their response - that's why ALL road fuel sold in the UK includes additives to keep the car's fuel system clean - those additives may vary slightly but since no fuel brand will publish their additive formulation that's supposition.

The same can be said of fuel-treatment additives - they probably duplicate the additives already in the fuel and they probably vary a bit.

I feel sure that additives will get improvements in a badly maintained engine - but I don't see how they can improve a well maintained engine - although I do add 50ml Millers Diesel Power Ecomax every 4th tank of fuel just to make sure it stays clean.

Testing is very difficult to do accurately - it needs to be done in a laboratory, under controlled conditions - so I personally disregard any "tests" by magazines, etc.

 

[GeorgeandAde]

Thanks for the replies.
Sounds like I could give the car a good run on the motorway once in a while to get everything "heated up" rather than spend money on a product that may or may not be beneficial.
The other thing ive heard about is "Terraclean".
Had the CRV motd recently and the garage said that they carry out this procedure and that they have had only positive response from motorists that have had this done.
Possibly another £133 not really needed.
Thanks once again.
Ade.

 

[seth1]

Correct a blast down the motorway is probably the best thing you can do.

 

[Sproket]

Thanks for the replies.
Sounds like I could give the car a good run on the motorway once in a while to get everything "heated up" rather than spend money on a product that may or may not be beneficial.
The other thing ive heard about is "Terraclean".
Had the CRV motd recently and the garage said that they carry out this procedure and that they have had only positive response from motorists that have had this done.
Possibly another £133 not really needed.
Thanks once again.
Ade.

Having just read the Q&A about How often do I need to have my vehicle TerraCleaned ? I nearly fell out of me chair laughing every 15,000 miles hmy: ..... having had the same diesel powered truck for the last seven years that has been regularly serviced by myself and running on supermarket diesel , I have tried this a couple of times out of curiosity, never had a problem with emissions or lack of power and I only do just over six miles to & from work...

Remember this

 

[GeorgeandAde]

Thanks once again.
I might try a bottle of that Millers additive and see what happens along with a few good runs on motorway now and again.
Thats the first time ive seen that advert from the 80s. Nice one

 

[ProfJohnL]

.................Testing is very difficult to do accurately - it needs to be done in a laboratory, under controlled conditions - so I personally disregard any "tests" by magazines, etc.

Hello Roger,
I think in this area of interest, whilst I would agree that some magazine tests may not stand up to close scientific scrutiny, if any of the claims made for these additives were shown to make significant differences, then that may have some value. But as it stands I have not seen any magazine report that suggests there is any clear or reliable improvements in cleaning or performance in fact it seems many of the so called performance enhancers actually reduce peak output power or torque. So perhaps Laboratory testing might show some consistent differences, but if it needs the precision of a laboratory to produce a measurable effect, then they're unlikely to produce any practical difference in the realities of real driving.

If any of these additives do have any real benefits then I agree they're more likely to show that benefit on a dirty engine than a clean one.

 

[Dustydog]

Our last diesel was regularly serviced every 10k. Up to 50K miles she was run on very little helps fuel. The EGR valve and turbo pipes failed due to getting oiled and gummed up. The car was rarely used on short journeys.
The Kia dealer blamed the fuel. Additives had been used at each service so did no good.
The next 75k a mixture of supermarket fuels and branded fuels were used .No problems.
Circumstantial evidence? Who knows?

 

[Mike_S]

I've never bothered using diesel additives in my Seat Alhambra but I do use Shell premium diesel fuel. The improved mpg more than offsets the extra cost and if it prolongs injectors, etc, so much the better.

Mike

 

[ProfJohnL]

I've never bothered using diesel additives in my Seat Alhambra but I do use Shell premium diesel fuel. The improved mpg more than offsets the extra cost and if it prolongs injectors, etc, so much the better.

Mike

Hello Mike,
Interesting post.
Most diesels need to run in to give their best MPG. So how do you know the Premium is actually responsible for your claimed better mpg?

 

[Mike_S]

Hello Prof
I fully agree with you comment re running in.
I bought my Seat from my local dealer with 2k on the clock (ex demonstrator) and for "my" first 8 to 10 k used ordinary or supermarket fuel. I calculated mpg using the "fill to brim" method for towing and solo driving.
It was reading Honest John in the Saturday Telegraph motoring section who advocated premium diesel for improved mpg, cleaner running, etc. Since then, and a further 14k miles I've used Shell premium (almost) exclusively.
Mpg has improved 8 to 10%. Any improvement in performance would be a more subjective assessment but I like to think that has improved as well!

Mike

 

[RogerL]

I reckon it takes 20-30,000 miles for a modern diesel to give of it's best.

 

[Mike_S]

My Seat is now at 26686!

Perhaps in the interests of experimental accuracy I should run a few full tanks of ordinary diesel through and see if there is an increase in consumption.

Mike

 

[JonnyG]

ummm...clean engine dirty engine? how on earth does one know how clean or dirty a 50k diesel engine is? or indeed a 25k engine mainly doing short runs,? unless you open the engine up take the injectors out take the turbo and egr valve off ect ect....then you wont know and nor will the fact that you have your car serviced regular guarantee its in A one condition where soot and sludge build up is concerned..although regular servicing of the oil and filters will help more than irregular services. cannot tell you if millers made my car any better nor if by using forte it cleaned my engine enough to make the £12 purchase worth it, but my emission test of this year mot in may, was the lowest i've seen in the 5 years ive run the tractor sounding engine i have in my mk3 Mondeo 2.2tdci and its had 130,000 miles to practice soot build up..until 2 years ago on cold starts especially in the winter it hunted for tick over common problem apparently egr valve injectors ect being the main cause, i started using millers regular and best grade fuel always, something i didn't do day in before. add the forte i use a month before Mot ...and that lumpy hunting tick over has gone, the mpg on long trips the only time i do proper calculations has gone up from 51 mpg ave over roughly 2500/3000 miles to 55 mpg.my times to the port from the port to Luxembourg to basle to.ect ect.. vary only slightly in time..so whilst its not a laboratory test
its as accurate as any magazine test and its been done over a longer period of time and greater mileage too..
sure i use additives for my own peace of mind for me that's what counts..

 

[RogerL]

but my emission test of this year mot in may, was the lowest i've seen in the 5 years

The MoT test doesn't test emissions for diesels - all it tests is the visual smoke using an opacity test.

 

[JonnyG]

but my emission test of this year mot in may, was the lowest i've seen in the 5 years

The MoT test doesn't test emissions for diesels - all it tests is the visual smoke using an opacity test.

call it what you want its emitted its measured and has a collaboration to how clean an engine is running..emission!
and indeed it was the lowest it has ever been in my 5 years of ownership.same egr valve same turbo same complete exhaust..no new pipes ect ect.. in other words nothing has changed but the soot test/smoke test emission build up call it what you like is lower !.. same mot station ..

 

[ProfJohnL]

Johnny
Have you lost your capital letters and carriage return, as your posts are more difficult to follow without these clear grammatical markers.

MOT tests are not absolute, the equipment they use will be calibrated and must operate within a specified range of uncertainty as compared to national standards. Even the same vehicle if tested several times consecutively will produce small variations in results.

Also its not uncommon for MOT stations to have to change equipment as it wears out, or becomes out dated, so even returning to the same station offers no guarantee of absolute consistency.

 

[JonnyG]

my Apologies for my lack of polished grammar,but as it a know fact that we humans a more than capable of understanding the gist of things i dont think it mattered that mucho.!
i agree with your comment about absolute certainties that's why this is only my opinion on the subject of additives based on My experience and what i have observed to happen over time.but then if my car is running more efficient based on my long run Mpg figures, its emission would be a tad lower it should therefore produce less soot per kg of fuel used and my yearly mileage doesn't alter that much therefore it is reasonable to assume the soot test would be lower regardless.but then that is my opinion..look forward to reading of your experience/s

 

[seth1]

Prof John L,i have just read your last post.I find it a bit hard to digest.By your reckoning an mot is not absolute.This meaning smoke test i presume and as Rodger pointed out measured by opacity as its always been.So are you saying the mot is not legiable or something else.I take on board your point of calibration,but all are calibrated to the same tolerance,which being a tolerance there will be a bit of room but not how your talking.I would think an mot centre would get tools calibrated more often than say a repair centre,after all it is a government run facility.
Non turbo charged diesel - 2.00
Turbo charged diesel - 3.00

 

[ProfJohnL]

Prof John L,i have just read your last post.I find it a bit hard to digest.By your reckoning an mot is not absolute.This meaning smoke test i presume and as Rodger pointed out measured by opacity as its always been.So are you saying the mot is not legiable or something else.I take on board your point of calibration,but all are calibrated to the same tolerance,which being a tolerance there will be a bit of room but not how your talking.I would think an mot centre would get tools calibrated more often than say a repair centre,after all it is a government run facility.
Non turbo charged diesel - 2.00
Turbo charged diesel - 3.00

Hello Seth,

I'm sorry, perhaps I didn't express my self clearly. so let me try again, I'm not questioning the legality of MOT station results. Provided the equipment is correctly calibrated. then the result can be considered legal. but its accuracy is quite coarse so the reading cannot be considered to be absolutely accurate.

The point is the calibration process has to include a degree of tolerance (as you point out). This means the same car could produce slightly different readings on different test sets, but also the same car can produce different results on the same test set, because there are so many variables that can affect the opacity of the exhaust gasses and small variances in the test sets measurement process.

 

[seth1]

Hello John ,you state the reading is quite "course" and compared to what?Another smoke tester of some description?Can there be a more accurate tester in a private garage than a Vosa test lane?My understanding is that the Vosa smoke tester is gospel,there is no arguing with it.On average it costs 40k to set a test lane up,spliting hairs comes to my mind.

 

[intransient1]

Hi Roger,
The one proven product to help keep the engine cleaner and reduce wear is Mobil 1 synthetic oil, but if you have a dpf fitted it will not clean that.
A 40 mile run at 40 mph will clean the dpf, but do it at least twice a month if you only do short local trips.